I messed up my whole career!

Hi all, 

I need your support more than ever as I messed up my career. 

To give some background, I am at my first work experience after college, I started my career in a large AM and working for this company was my dream since college.

Everything was amazing till the arrive of a new manager. He is a complete psycho, manipulative and abusive and he targeted me since day 1 because I was shining at that time and he saw me as a competitor.

Since then, I did something that should never be done: I fought back. 

I had solid proves against him (he sabotaged me several times) and at first I believed to have some chances to win in this situation. Long story short, senior managers didn't want issues and they tried to put everything under the rug. 

The situation with this person got worst and worst as he is vindictive and I am at the point that it's deeply affecting my mental health. 

I know I should have left the firm long time ago but I was still hoping things would have somehow fixed or get better. 

I even told him that I have intention to leave the team so I am not a competitor anymore but he doesn't care, he is making my life impossible. 

I have a good academic background but interviewing with this situation that is draining my mental energy is not easy. 

At this point, I am so desperate that I am willing to accept everything to escape this nightmare and then set up and start a proper job search for what I like doing. On the other hand, I don't want to ruin my career and make desperate moves that I will regret forever.

Am I being an idiot for thinking to change for a less better position (any at this point) and leave a prestigious company without a good option in my hands? 

If you faced similar situations, how did they end up?

Thanks a lot!